Maine tidal power company completes tests of river technology

EASTPORT, Maine — Ocean Renewable Power Company, which is developing equipment to harness tidal currents to generate electricity, completed testing of similar technology that would provide power to a rural village in Alaska, company officials announced this week.

The company completed tow testing of its RivGen turbine generator unit in the waters near Eastport, a cooperative effort with the Maine Maritime Academy and the Eastport Port Authority.

The redesigned proprietary river power system has improved reliability and durability, said company officials in an announcement issued Monday. The unit will be shipped to Alaska this summer for its first commercial-scale demonstration.

The RivGen unit is destined for the southwestern Alaska village of Igiugig on Lake Iliamna at the mouth of the Kvichak River. The system will be installed in the Kvichak River for several months of operation this summer. The village has about 50 year-round residents, although the number swells during the summer.

The RivGen power system is a submersible hydrokinetic system designed for smaller river applications in water depths of 15 feet or more, including those in remote, off-grid or micro-grid communities.

“We have focused on these markets where there are remote communities,” Chris Sauer ORPC president and CEO, said Tuesday from the company’s Portland offices — communities like Igiugig, for example, that rely on diesel generators for micro-grids.

The cost of providing power in such remote villages is very high, he noted, because they use diesel fuel.

“Right now, until we get further down the road, we can’t compete with the grid price of power,” said Sauer. “But in a few years, we will.”

There likely will be some applications for the technology in Maine, he said, although that is not the target.

“We’re looking for rivers that have greater water speeds than in Maine,” he said, such as in Alaska, Canada and Chile.

One potential application in Maine could be the raceways of hydroelectric power stations. The company’s RiverGen system conceivably could augment those power facilities.

Sauer also said the company has identified design improvements for the tidal generating turbine it has deployed near Eastport in the past for testing. The equipment was removed from the water last summer for maintenance and originally was scheduled to be improved and returned to the waters for more testing.

“We know too much,” said Sauer. Instead of “patching up” the old turbine, which resembles a huge rotary lawnmower, the company will build a new one. It has been awarded $5 million in federal grants to help accomplish that.

The new technology should be ready toward the end of the year or in 2015, said Sauer, and will undergo testing. After that, the company will look at expanding the use of its technology into the Western Passage of the Passamaquoddy Bay.

ORPC will use its licensed site in Cobscook Bay later this year to test a prototype mooring and anchoring system for its tidal turbine generators.

ORPC began operation of the Cobscook Bay Tidal Energy Project in 2012, the first commercial, grid-connected hydrokinetic tidal energy project in North America using the company’s proprietary TidGen power system.